A phase shifter is a core component of a base station antenna. A phase shifter that is developed currently not only can adjust a phase but also can adjust an amplitude. In this way, the phase shifter can adjust a pointing direction of a radiation pattern formed in space by the base station antenna, so as to flexibly adjust coverage of different user regions. Performance of the phase shifter not only affects indicators such as gain, a pattern, and isolation of the antenna, but also affects a size and costs of the antenna.
Solution in the prior art: high-frequency cavity phase shifter:
FIG. 1 shows a cavity phase shifter. The cavity phase shifter includes a housing 1, a cavity disposed inside the housing 1, a substrate 3 located inside the cavity, a conductor 4 disposed on the substrate 3, and movable dielectrics 2 disposed on two sides of the substrate 3.
A movable dielectric or air may be used as a substrate of the shown conductor 4. The shown movable dielectrics 2 include an upper part and a lower part. The conductor 4 is fastened in the movable dielectric 2. The movable dielectric 2 freely slides in a cable layout direction of the conductor 4, to change a location at which the movable dielectric covers the conductor 4 and an area that the movable dielectric covers on the conductor 4. In this way, a dielectric constant of a propagating signal is affected. That is, a phase of an output signal is changed, so as to perform phase shifting.
FIG. 2 is a connection diagram of a conventional multi-band antenna network (Note: CMB represents a combiner). Phase shifters and combiners are separately designed, resulting a large quantity of cables and a complex layout. As more frequency bands are integrated by a single-sided base station antenna, it is increasingly difficult for such a network connection to meet a requirement.